For visual help, draw a right triangle with an acute angle of 46°:
Since the sum of the internal angles of a triangle is 180°, then:
[tex]46+90+\text{?}=180[/tex]since 46+90=136, then:
[tex]\begin{gathered} 136+\text{?}=180 \\ \Rightarrow?=180-136 \\ \Rightarrow?=44 \end{gathered}[/tex]Therefore, the other acute angle has a measure of 44°.
The student may have forgot to include the angle of 90° into account, thinking that the remaining angle should add up to 180° with the 46° angle, without adding the 90° from the third angle.
